I wound up using a vintage Benjamin 273 Peep. It was period correct upgrade to the factory open blade sight.Rob compared it to the older "Bar-O" here...https://www.gatewaytoairguns.org/GTA/index.php?topic=128390.0
I shoot mainly 28g Eun Jins in my Steroided 342 & 18g JSBs in my stock 342. I use the Mac-1 IA mount on my 342s & Sheridan Blue & Silver Streaks. Doesn’t promote barrel separation, is rock solid & can be breech or scout mounted. http://www.mac1airgunshop.com/mobile/Product.aspx?ProductCode=BJSHIA